not every change in upstream will make firehose change definitions and not every change in definitions is a change we care about, I don't know how changes in definitions are evaluated these days, I think all my logic for that has been reverted

ssam2: The lipstick for the pig would be something consuming a description of the pipeline (which we could generate as we generate the buildbot and firehose configs) and consuming that JSON API in some fashion

having CIAT keep track of which systems are built in order to trigger deploys of clusters depending on multiple systems will depend on the artefacts not being removed, is this okay for now or too hacky?